Improvements

- Introduced an a tag on the title h1, which points always at the root of the calendar

- Second commit introduces 2 files in static (tableUI.*) which adds a script found on stackoverflow and adapted, it adds a nice jqueryUI behaviour on the table. I refactored get_header_tags introducing some parameters for versions and themes (to be set elsewhere in the future?), there's a new function create_plain_link to get only the link (I didn't understood how to do simpler). Lastly there's the usage on div.phpc-date of this function to allow the clicking on the whole area.

- Third commit: change in calendar php to add in menus a &nbsp; instead of spaces (when resizing windows makes menu entry to go completely into new row); css has less colors (and rgb instead of names), default font is verdana, and some sizes are changed. At the top, after license, there's a little color key to facilitate search and replace. Finally the footer uses a new css class in common with the top menu (retains the old classes, but they are empty..) The event description has no more style for now.

- In the fourth commit I gave some classes to elements in the event display page.

- Fifth fixes a bug, in the admin options was set the start of the week, but in the jquery datepicker the week started always on default.